Microbiology Unknown free essay sample

Read the Latex Agglutination Test information provided and answer the following: 1. What does agglutination mean? Clumping of bacteria or red cells when held together by antibodies. 2. Since we are in microbiology we are looking for the clumping of Epitopes found on the surface of Antigen that will bind to specific Antibody that were made by Immune system(B cells). 3. What will a positive result look like? Clumping. 4. What will a negative result look like? Dilute liquid no clumping. Latex Agglutination Test The latex agglutination test is a laboratory method to check for certain antigens in a variety of bodily fluids including saliva, urine, cerebrospinal fluid, or blood. The sample is mixed with latex beads coated with a specific antibody. If the suspected substance is present (the specific antigen), the latex beads (with the specific antibody) will clump together with the antigen (agglutinate). AntigenAntibodyattached to beads in liquid When the antigen shape matches the antibody shape, they will bind to each other and the cells/antibody/antigen will clump together (as below). We will write a custom essay sample on Microbiology Unknown or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page Notice how the dark spots are clumping in the liquid. When the antigen shape does not match the antibody shape, they will not bind to each other (see below). Notice that there are no clumps in the liquid. Procedure a) Place a drop of the Latex Control liquid in one of the circles on the test card. The Latex Control liquid will have the liquid contain the latex beads with no antibodies attached. b) Aseptically remove a colony from an agar plate and place it on the circle with the Control liquid. c) With the sterile loop, mix the liquid with the colony. d) Place a drop of the Latex Test liquid in the second circle on the test card. The Latex Test liquid will have the liquid with antibodies for a specific microbe (in our class, the antigen is for Staph aureus) attached to the latex beads . e) Aseptically remove a colony from an agar plate and place it in a second circle marked on the test card. f) With the sterile loop, mix the liquid with the colony. ) Compare the mixtures of the two colonies. 5. In the space below, diagram the results of the Agglutination Test. Use color where appropriate. Preparing for class Day 1 Read the Enterotube II System information provided and answer the following: 1. What types of bacteria will the Enterotube II Test identify? E coli. 2. What informa tion will the Enterotube II Test give us? ID gram-neg, glucose fermenting, oxiase-negative enterobacteriaceae. The Enterotube II System The basic philosophy of the Enterotube II System is the speed, ease and low cost in the identification of gram negative, glucose fermenting, oxidase-negative Enterobacteriaceae. The Enterotube II System consists of a single tube containing 12 compartment, each containing a different agar culture medium. There are compartments that require aerobic conditions and have small openings that allow air in; those compartments that require anaerobic conditions have a layer of paraffin wax on the top of the media. There is a self- enclosed inoculating needle or wire that runs through the center of the tube. The end of the needle can touch an isolated bacterial colony and then in one movement can be drawn through the 12 compartments so that every compartment is inoculated. [pic] After 18-24 hours of incubation, the color changes that occur in each of the compartments are recorded and interpreted according to the manufacturer’s instructions. The interpretation is done by determining a five-digit code from the results and then consulting a coding manual. [pic] Inoculating the tube: a. Remove the caps from both ends of the Enterotube. The tip of the wire is sterile and does not need to be flamed. b. Touch a well-isolated colony from an agar plate with the tip of the wire. c. Inoculate the Enterotube with the bacterial culture by drawing, and at the same time rotating, the wire through the 12 compartments. d. Push the wire back through the Enterotube so that the 12 chambers are re-inoculated. e. Withdraw the wire once again until the tip is in the H2S/indole compartment and then break the wire at the notch by bending it back and forth. f. Replace the caps but do not tighten.